Maybe a summation of things that I hope will be of help on your next cook will be useful. Not anything really new, just collated -
1. ALL turkeys
unless they specifically say otherwise on the packaging.. are already brined by the turkey processor. This assures more cooks get a juicy bird -
and it adds water weight..which you pay for at turkey price per lb. ! So, additional brining really does not help anything, other than make sure the skin is full of moisture.
2. The skin moisture ( mostly water - some fats) is the problem that many face - when their turkey or chicken turns out with rubbery skin. But, in this case it did cause additional problems.
3. The skin that was "bulked up" with the additional wet brine + the wet wood created a good deal of steam. Steam will cause more of the sooty smoke to stick to your bird.
What seems to wok well for me is to remove a typical bird from he shrink wrap, rinse, remove the bagged innards and neck, and look it over for pin feathers.. Dry it off, and place it on a wire rack above a pan to catch any drips. Place the pan with turkey in a refrigerator for 24 hours - up to 48 will not hurt. The refrigerated air is dry - so it helps the moisture that is in the skin to evaporate. Don't worry - the drying skin continues to act as a barrier for the meat of the bird, and it will remain moist.
So - after the 1-2 days- bring the bird out and set it on the counter - still on the wire rack, and spritz it
very lightly with oil. urn it over and repeat on the backside, under the wings, etc. I like to use Pam - as it is canola - and has no taste, but use what you like. Then apply whatever rub or seasonings you desire.
Now - when you are prepping you charcoal allow it to stop producing a lot of white , dense smoke before you put the turkey on. You may want to consider mixing some good quality lump charcoal in with your KBB. It will increase the temp. of your fire. I find the target temp of approx. 325-350F to work best for me. So - I also advise that if you have a 2 channel remote digital thermometer ( Maverick 732, 733, 734 are all great...) And use on probe to monitor pit temp and one in the breast or thigh of the bird. This will help you accurize your cook - and help you learn your pit's cooking personality. It will also help you see what the effect of any change you make in your vent settings.
Hope this helps!